1897.] Zoology. 629 
forestalled at their very beginnings. Thus it has been usual for philoso- 
phers, like Lamarck, Nägeli and Eimer, to assume that the exact repro- 
duction of likeness was the original characteristic of organic reproduc- 
tion, and that variability is an anomaly to be accounted for. This is 
now met by Bailey’s contra-assumption that unlikeness marks all un- 
sophisticated reproduction, and that “heredity is an acquired char- 
acter.” Both are equally assumptions and equally gratuitous. What 
we actually know is that among different races the average degree of 
likeness between successive generations differs. We also know that the 
degree of likeness fluctuates from generation to generation in the same 
race. + We do not know of such a thing as absolute likeness, nor do we 
know the complete absence of heredity. The only thing that we do 
know is that similarity begets similarity. That like begets like, or 
unlike begets unlike can be true only by a quibble of the terms. 
In dealing with this subject in a very critical class of students we 
have so much felt the need of more precise nomenclature that I have 
given the name of the allophysical law to the formula “similarity be- 
gets similarity.” Heredity is then retained in its absolute sense (the 
sense in which it is actually most used) as a convenient zero-point from 
which to measure variability. But the normal cause of reproduction 
is not conceived to be the repetition of exact likenesses, nor of total un- 
likenesses, but is understood to follow the allophysical law, —F. A. 
Wavuaeu. 
Zoological News.—<According to Mt. E. H. L. Schwartz, Spirula 
is in its anatomy closely related to Sepia. As to its descent the author 
finds that it has been derived from the Belemnites through Spiruliros- 
tra, thus reversing the process set forth in an authoritative article 
recently published. - Mr. Schwartz bases his conc] the study 
of sections of the shell passing through all the whorls in a the plane of 
coiling, whereby the structure of the walls and septa are well exposed. 
(Journ, Marine Zool. and Micros., Vol. II, No. 6.) 
Nineteen species and subspecies of Voles are recognized by Mr. 
Bailey as inhabiting Canada and the United States. Of these, five are 
described as new. Concerning the habits of these animals the author 
states that they do not hibernate in winter, nor has he ever found evi- 
dence of their storing provision. They make long tunnels under the 
snow, through which they travel about in safety while they procure the 
tender grass blades and ripe seeds as easily from the surface of the 
ground as when the white blanket is not above them. (Proceeds. 
Biol. Soe. Washington, Vol. XI, 1897.) 
